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ESE MSX System 3 information

Written by Albert Beevendorp and Patriek Lesparre.

Contents

1. DIP switches
2. Special keys
3. USB ports
4. Loading System ROMs from SD-card
• Description of the boot procedure (IPL ROM)
5. Known issues
6. VGA Connector pin-out
7. Programming the FPGA with a cable
8. Software
9. Slot layout
10. SDRAM layout
11. Using disk images
12. ESE-RAM and ESE-SCC

DIP switches

The dipswitch block on the bottom side of the ESE3 (held sideways) looks a bit like this:

Special keys

USB ports

With the currently available FPGA code, the USB ports only act as a power source. So you can use it to recharge USB devices, or power USB lights and fans. To connect a USB keyboard, use a USB to PS/2 convertor (Note: Some USB to PS/2 convertors only work for mice)

Loading System ROMs from SD-card

• the SD-Card must be FAT12 or FAT16 formatted
• when using loose files the max. cluster size is 16 kB. Larger cluster sizes need the ROM images concatenated into one 256kB file.
• the ROM images must be the VERY first file(s) on disk and be unfragmented
• the ROM images are loaded from sector in order:
  • MEGA-SD.ROM (64 kB)
  • MSX2BIOS.ROM (32 kB)
  • MSX2SUB.ROM (16 kB)
  • MSXMUSIC.ROM (16 kB)
  • KANJI font ROM (128 kB)

Description of the boot procedure (IPL ROM)

• copy IPL ROM contents from 0000h to F000h:
• set palette and execute contents at F000h
  • read boot sector
  • find 'FAT' text, copy ROMs from flashROM if not found
  • find first DATA sector
  • read the sector
  • check for 'AB' signature, copy ROMs from flashROM if not found
  • read sectors and copy ROMs from SD-card

Known issues

• OPLL doesn't get fully silenced after reset
• SCC-I seems to skip data or something
• missing slot sound input volume
• keyclick is mixed with PSG volume
• TEXT80 mode second color misses actual blinking
• sunrise logo animation is quite slow
• xak 1 sound corruption causes game to fail
• lacks keyboard matrix key ghosting
  (ghosting is caused by real MSX keyboard)
• VGA display is stretched (some columns are 2 pixels wide)

VGA Connector pin-out

Programming the FPGA with a cable

If you accidentally programmed a non-working .pld into the FPGA, you can reprogram it directly by way of an internal connector on the ESE3, marked J14. This connector provides access to the FPGA chip using the 'active serial' protocol. (Note: JTAG and 'passive serial' are not supported!)

Here is a schematic for a Parallel port digital ByteBlaster II cable, provided by Edwin Velds, which can be used for this purpose.

The user guide for this cable can be found here. You can get the Altera Quartus II Programmer software here.

Software

Download the ESE3 software here. Here's a description of the most interesting files:

• ESEMSX3\board\emsx_pcb.pdf
  - ESE3 Printed Circuit Board design
• ESEMSX3\board\emsx_sch.pdf
  - ESE3 Circuit Diagram
• ESEMSX3\pld\emsx_top.hex
  - MSX System ROMs in Intel Hex format.
• ESEMSX3\pld\emsx_top.pld
  - This file contains configuration data for the FPGA, the compiled VHDL code. Simply put, this is the MSX system. NOTE: This file is slightly newer than the factory default FPGA contents.
• MSX-DOS2\FAT16\
  - MSX-DOS2 system files for FAT16.
• MSX-DOS2\Original\
  - Complete MSX-DOS2 environment.
• TOOLS\DiskImage\EP.COM
  - A floppy disk emulator, to use disk images as if real disks.
• TOOLS\DiskImage\FDLOAD.COM
  - Writes a disk image to a real disk.
• TOOLS\DiskImage\FDSAVE.COM
  - Creates a disk image from a real disk.
• TOOLS\DiskImage\reference\BU951030.LZH\FDCOPY.COM
  - A disk copy program.
• TOOLS\DiskImage\reference\BU951030.LZH\MGLOAD.COM
  - Load a ROM image into the ESE-SCC/RAM.
• TOOLS\DiskImage\reference\BU951030.LZH\MGSAVE.COM
  - Creates a ROM image from a real cartridge.
• TOOLS\PLDLOAD\PLDLOAD.COM
  - Load a .pld configuration file into the ESE3 FPGA.
• TOOLS\PLDLOAD\PLDSAVE.COM
  - Save the current configuration of the ESE3 FPGA.

For compiling and synthesizing the VHDL source code you will need Altera's Quartus II Web Edition software. Version 8.0 has been reported to have problems, so please download version 7 here.

Slot layout

SDRAM layout

Using disk images

Using DIP switch 5, the Mega-SD support can be switched on or off. It has support to emulate a floppy disk drive with a disk switch option. An extra table is kept with room for up to 16 disk images. A disk image can be connected to a drive letter, so it's possible to access the disk image as if it was a real diskette. To use the feature there's a tool available on the CD-ROM called EP.COM. It's located in the TOOLS\DiskImage directory.

EP.COM adds a disk image to the table and either connects it to a drive letter for direct use or prepares it for a multi-disk use. Disk images can be made read-only when adding it to the list. Remember to keep a game's user disk write enabled.

To switch a disk image, keep the KANA key (F7 on a PS/2 keyboard) pressed while taking the action the running software requires to continue loading. The CAPS LOCK LED will blink, indicating that it's ready to accept a key press on the numeric pad which will indicate the disk to be switched. A table of each possible key and the corresponding disk image number is displayed below:

It's only possible to use a drive letter assigned to the Mega-SD to connect to a disk image. Some disk image connect examples:

• EP DOCUMENT.DSK B: /W
  Connect DOCUMENT.DSK to driveletter B: and make it read-only (with /W). When there's already a disk image connected to it, there will be an error and it won't be connected.


• EP TOOLS.DSK B: /F
  Connect TOOLS.DSK to driveletter B:. When there's already a disk image connected to it, it'll be disconnected (with /F) before it's connected.

Single-disk example: Undeadline (filename UNDEAD.DSK):

• EP UNDEAD.DSK /B /R
  The disk image is added to the table and set as boot disk (with /B) and the system will reboot using the disk emulator (with /R) to boot the disk.

Multi-disk example 1: Ancient Ys Vanished The Final Chapter (filenames YS2-PROG.DSK and YS2-DATA.DSK, in that order on the disk):

• EP YS2-*.DSK /B /R
  The disk images are added as they are found, the first disk image in the table is set as boot disk. Assuming the table is empty, it'll look like this:
  0 : YS2-PROG.DSK
  1 : YS2-DATA.DSK

Multi-disk example 2: Xak - The Tower of Gazzel (GAZZEL1.DSK, GAZZEL2.DSK, GAZZEL3.DSK and GAZZEL4.DSK, in any order on the disk):

1. EP GAZZEL1.DSK /B /D
   First an existing table is cleared (with /D) and the disk image is added and set as boot disk.
2. EP GAZZEL2.DSK
   The disk image is added to the table.
3. EP GAZZEL3.DSK
   The disk image is added to the table.
4. EP GAZZEL4.DSK /R
   The disk image is added to the table, and the system will reboot using the disk emulator to boot the disk. The table will look like this:
   0 : GAZZEL1.DSK
   1 : GAZZEL2.DSK
   2 : GAZZEL3.DSK
   3 : GAZZEL4.DSK

Multi-disk example 3: Aleste 2 (filenames ALESTE2D.DSK, ALESTE21.DSK and ALESTE22.DSK, in that order on the disk):

• EP ALESTE2*.DSK /B1 /R
  The disk images are added as they are found, the disk image on number 1 in the table is set as the boot disk (with /B1). Once the table is set up the system will reboot using the disk emulator to boot the disk. Assuming the table is empty, it'll look like this:
  0 : ALESTE2D.DSK
  1 : ALESTE21.DSK
  2 : ALESTE22.DSK
  The number behind the /B option is written in hexadecimal notation. It corresponds with the number or letter printed before the colon.

Multi-disk example 4: SD-Snatcher (filenames SDSNATUS.DSK, SDSNAT1.DSK, SDSNAT2.DSK and SDSNAT3.DSK, in any order on the disk):

1. EP SDSNATUS.DSK /D
   The table is cleared and the user disk image is added.
2. EP SDSNAT1.DSK /B /W
   The disk image is added to the table, set to read-only (with /W) and set as boot disk.
3. EP SDSNAT2.DSK /W
   The disk image is added to the table and set to read-only.
4. EP SDSNAT3.DSK /R /W
   The disk image is added to the table and set to read-only, and the system will reboot using the disk emulator to boot the disk. The table will look like this:
   0 : SDSNATUS.DSK
   1 : SDSNAT1.DSK
   2 : SDSNAT2.DSK
   3 : SDSNAT3.DSK

The disk images must be unfragmented on the disk to work. This will be checked by EP just before it's added to the table.

ESE-RAM and ESE-SCC

Using DIP switches 7 and 8 the function of slot 2 can be selected. Setting them up to both off, the second cartridge slot is available (to access through slot), otherwise one of the ESE-RAM or ESE3-SCC is enabled in slot 2. When one of those devices are enabled, there is 512 kB RAM extra which is mapped by the device selected. This can be the SCC, ASCII 8kB or ASCII 16kB. The RAM can be used to load MegaROM files. For this there's a tool available on the CD-ROM called MGLOAD.COM. It's archived in BU951030.LZH which is located in the TOOLS\DiskImage\reference directory.

MGLOAD.COM detects the used MegaROM mapper and then loads the file in the RAM. It doesn't detect in which slot the device is and therefore the user is required to provide this slot. In this case it's slot 2. Some examples:

Example 1: load Zanac-Ex (filename ZANAC-EX.ROM):

1. Set up the ESE-RAM ASCII 16 kB mode (DIP 7 on, DIP 8 on).
2. Switch on the ESE3.
3. In MSX-DOS, type MGLOAD ZANAC-EX.ROM /S02

Example 2: load Mon Mon Monster (filename MONMON.ROM):

1. Set up the ESE-RAM ASCII 8 kB mode (DIP 7 on, DIP 8 off).
2. Switch on the ESE3.
3. In MSX-DOS, type MGLOAD MONMON.ROM /S02

Example 3: load Metal Gear 2 Solid Snake (filename SSNAKE.ROM):

1. Set up the ESE3-SCC mode (DIP 7 off, DIP 8 on).
2. Switch on the ESE3.
3. In MSX-DOS, type MGLOAD SSNAKE.ROM /S02

The /S02 refers to the slot of the ESE-RAM. It's possible to play non MegaROM titles with the device as well. ESE3-SCC is best suited to run those titles. As MGLOAD doesn't restore mapper banks to the initial state, a reset of the ESE3 after loading is required to start it.

Alternatively, you can use ROMLOAD for ROM images in SCC mode.